Total energy usage increased by 1% from 234,485 MWh in 2007 to 237,842 MWh in 2008. However, when normalised to take account of business growth, there was the equivalent of a 16% decrease. Since 2003, absolute energy usage has increased by 3%, with an equivalent 25% decrease in normalised terms.
In 2008, we continued to expand the number of locations purchasing renewable electricity; renewables provide 12% of our total electricity needs and 10% of our total energy.
Although 92% of RE facilities are offices, they are only responsible for 63% of our energy usage. Energy usage at our offices decreased 1% in absolute terms between 2007 and 2008. Data centres were responsible for 34% of our energy in 2008, a 5% increase over 2007. This correlates to a 6% increase in the number of searches conducted in the year, and a 21% increase in information storage.
Our data centre working group is improving efficiency through consolidation and virtualisation, cooling control and the purchase of more efficient hardware. In 2008, we began working with Energy Star on a new rating for data centres and contributed to a study by the Uptime Institute on green data centre standards. In 2008, the average PUE of our data centres was 1.90, better than the US average of 1.97.